This new G-SHOCK was engineered for those special secret missions that demand precision and stealth. The countdown timer function has a large, easily identifiable button for direct access and sure operation under the toughest of conditions. At the end of a countdown, alerts are issued by either a vibration or a tone plus LED flash operation. The large face of the GD350 is configured to ensure that the countdown timer is easily seen in the dark. A high luminance LED can be configured to light up for one, three, or five seconds, and an Auto Light feature. Shock Resistant 200M Water Resistant Auto LED Backlight Super Illuminator Flash alert Flasher with buzzer that sounds for alarms, hourly time signal, countdown timer time-up alarm World Time 35 time zones 100 cities UTC , city code display, daylight saving on/off. Round sport watch with LED digital display featuring day, date, and time 53.4 mm resin case with mineral dial window Water resistant to 200 m 660 ft In general, suitable for professional marine activity and serious